~4- poy OM TTRET ene roe — =. ae ce fee fe aa { PpSo + . La ky “ab concentration-latitude profile was obtained by simply drawing a continuous curve through the available data points. From this curve the average fallout concentration expected in ground level air at the latitude of Bikini Island qai1° 37. N) should be approximately . 32 aci/m?. This value cannot be considered to be in disagreement with the mean concentration detected on the lesser contaminated island of Eneu.”? 5 However, it is not only well below the log normal median (134 aci/m>) or mean (186 aci/m>) concentrations on Bikini Island but 1s well below the range found over the entire Island. There is little question that the plutonium levels in air during June 1970 were above fallout background _ levels for the latitude of Bikini Island. The only mechanism by which these levels could have been attained was through resuspension processes on the Island. The median value at Bikini is very nearly equivalent to the ~ mean air concentration at New York ‘during this period. It should be remembered that during 1970 the urine concentrations from Bikini and New York were also. comparable. Except for water, no other indigenous material was consumed at Bikini during the two years before 1970. From this comparison of New York and Bikini, the 1970 data strongly suggests there was a close correlation between aeolian plutonium levels and urine concentrations. | In May 1972, air samplers were again operated on Bikini Island at four different locations. Th e 239,240 Pu air concentration during this period ranged from less than to 6 to 80 aci/m,!° The log normal median concentration over the Island was 21 aci/m and the mean concentration was 34 aCi/m>. } In Fig. 2 are plotted the HASL plutonium air concentrations during May 1972 as a function of latitude. !! £ L MMB cti A smooth continuous curve | il vaad be